feat(layout): add tamil99 layout (@ving-sh) (#7313)

### Description

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### Checks

- [ ] Adding/modifying Typescript code?
  - [ ] I have used `qs`, `qsa` or `qsr` instead of JQuery selectors.
- [ ] Adding quotes?
- [ ] Make sure to include translations for the quotes in the
description (or another comment) so we can verify their content.
- [ ] Adding a language?
- Make sure to follow the [languages
documentation](https://github.com/monkeytypegame/monkeytype/blob/master/docs/LANGUAGES.md)
  - [ ] Add language to `packages/schemas/src/languages.ts`
- [ ] Add language to exactly one group in
`frontend/src/ts/constants/languages.ts`
  - [ ] Add language json file to `frontend/static/languages` 
- [ ] Adding a theme?
- Make sure to follow the [themes
documentation](https://github.com/monkeytypegame/monkeytype/blob/master/docs/THEMES.md)
  - [ ] Add theme to `packages/schemas/src/themes.ts`
  - [ ] Add theme to `frontend/src/ts/constants/themes.ts`
  - [ ] Add theme css file to `frontend/static/themes`
- [ ] Add some screenshots of the theme, especially with different test
settings (colorful, flip colors) to your pull request
- [x] Adding a layout?
- [x] Make sure to follow the [layouts
documentation](https://github.com/monkeytypegame/monkeytype/blob/master/docs/LAYOUTS.md)
  - [x] Add layout to `packages/schemas/src/layouts.ts`
  - [x] Add layout json file to `frontend/static/layouts` 
- [ ] Adding a font?
- Make sure to follow the [themes
documentation](https://github.com/monkeytypegame/monkeytype/blob/master/docs/FONTS.md)
  - [ ] Add font file  to `frontend/static/webfonts`
  - [ ] Add font to `packages/schemas/src/fonts.ts`
  - [ ] Add font to `frontend/src/ts/constants/fonts.ts`
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(https://www.conventionalcommits.org for more info)
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tag them below.
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[Discussion
#6483](https://github.com/monkeytypegame/monkeytype/discussions/6483)

Layout Documentation
https://learn.microsoft.com/en-us/globalization/keyboards/kbdtam99
http://kbdlayout.info/KBDTAM99?arrangement=ANSI104

---------

Co-authored-by: Jack <jack@monkeytype.com>

frontend/static/layouts/tamil99.json

@@ -0,0 +1,62 @@
+{
+  "keymapShowTopRow": false,
+  "type": "ansi",
+  "keys": {
+    "row1": [
+      ["`", "~"],
+      ["1", "!"],
+      ["2", "@"],
+      ["3", "#"],
+      ["4", "$"],
+      ["5", "%"],
+      ["6", "^"],
+      ["7", "&"],
+      ["8", "*"],
+      ["9", "("],
+      ["0", ")"],
+      ["-", "_"],
+      ["=", "+"]
+    ],
+    "row2": [
+      ["ஆ", "ஸ"],
+      ["ஈ", "ஷ"],
+      ["ஊ", "ஜ"],
+      ["ஐ", "ஹ"],
+      ["ஏ"],
+      ["ள"],
+      ["ற", "ஶ"],
+      ["ன", ":"],
+      ["ட", "["],
+      ["ண", "]"],
+      ["ச", "{"],
+      ["ஞ", "}"],
+      ["\\", "|"]
+    ],
+    "row3": [
+      ["அ", "௹"],
+      ["இ", "௺"],
+      ["உ", "௸"],
+      ["்", "ஃ"],
+      ["எ", "எ"],
+      ["க", "க"],
+      ["ப", "ப"],
+      ["ம", "\""],
+      ["த", "௱"],
+      ["ந", ";"],
+      ["ய", "'"]
+    ],
+    "row4": [
+      ["ஔ", "௳"],
+      ["ஓ", "௴"],
+      ["ஒ", "௵"],
+      ["வ", "௶"],
+      ["ங", "௷"],
+      ["ல", "ௐ"],
+      ["ர", "/"],
+      [",", "<"],
+      [".", ">"],
+      ["ழ", "?"]
+    ],
+    "row5": [[" "]]
+  }
+}

packages/schemas/src/layouts.ts

@@ -231,6 +231,7 @@ export const LayoutNameSchema = z.enum(
     "persian_farsi_colemak",
     "persian_standard_colemak",
     "ergo_split46",
+    "tamil99",
   ],
   {
     errorMap: customEnumErrorHandler("Must be a supported layout"),